ladybird/Kernel/Syscalls/sendfd.cpp
Andreas Kling b56646e293 Kernel: Switch process file descriptor table from spinlock to mutex
There's no reason for this to use a spinlock. Instead, let's allow
threads to block if someone else is using the descriptor table.
2022-01-29 02:17:09 +01:00

57 lines
1.7 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/FileSystem/OpenFileDescription.h>
#include <Kernel/Net/LocalSocket.h>
#include <Kernel/Process.h>
namespace Kernel {
ErrorOr<FlatPtr> Process::sys$sendfd(int sockfd, int fd)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
TRY(require_promise(Pledge::sendfd));
auto socket_description = TRY(open_file_description(sockfd));
if (!socket_description->is_socket())
return ENOTSOCK;
auto& socket = *socket_description->socket();
if (!socket.is_local())
return EAFNOSUPPORT;
if (!socket.is_connected())
return ENOTCONN;
auto passing_description = TRY(open_file_description(fd));
auto& local_socket = static_cast<LocalSocket&>(socket);
TRY(local_socket.sendfd(*socket_description, move(passing_description)));
return 0;
}
ErrorOr<FlatPtr> Process::sys$recvfd(int sockfd, int options)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
TRY(require_promise(Pledge::recvfd));
auto socket_description = TRY(open_file_description(sockfd));
if (!socket_description->is_socket())
return ENOTSOCK;
auto& socket = *socket_description->socket();
if (!socket.is_local())
return EAFNOSUPPORT;
auto fd_allocation = TRY(m_fds.with_exclusive([](auto& fds) { return fds.allocate(); }));
auto& local_socket = static_cast<LocalSocket&>(socket);
auto received_description = TRY(local_socket.recvfd(*socket_description));
u32 fd_flags = 0;
if (options & O_CLOEXEC)
fd_flags |= FD_CLOEXEC;
m_fds.with_exclusive([&](auto& fds) { fds[fd_allocation.fd].set(move(received_description), fd_flags); });
return fd_allocation.fd;
}
}